Have you tried fully removing the sensor(s) from your hub (red Remove button at the bottom of the device page) and then resetting re-adding them? I have had some devices that have required that to report properly.
If you have the sensor in apps for automations, you can use Swap Apps Device (Settings>Swap Apps Device) to temporarily swap the Sengled with a virtual contact sensor you create, then swap the real device back in after you've re-join the real sensor. That way you won't break your automations by removing the sensor.
I reset them and re-added them “successfully”, but same experience. I let them sit for an hour to see if they will report…nothing. Maybe my Hubitat unit is too old as a C-5.
I had used Sengled bulbs w/out issue for quite a while on my C7, until I started having problems last year w/them dropping off my C7. The Sengled bulbs included bright white (equiv 100w), classic white, and color bulbs. Never figured out what was going on, and experienced the same issue on my C8. (Along w/other Zigbee devices, I was having the C8 Zigbee issues across most of my Zigbee devices.) Some (on C7 & C8) have reported similar issues, others have used Sengled bulbs w/out problems. I ended up replacing the Sengled w/Hue bulbs as I already had the Hue bridge in use w/some other bulbs.
FWIW, I've got ~120 zigbee devices, mix of 1.2 and 3.0 mains powered repeaters, and all my battery powered Zigbee devices are 1.2 (Iris v2/v3 motion, Visonic MCT-340 contact, Aqara contact, Samsung & Centralite leak). Single-story ranch, about 2500 sqft, hub is relatively central in the house, stock antenna.
I've had a big chnage in the past couple of weeks - I have somehow magically gotten to the point on my C8 where Zigbee is holding solid. Radio hasn't rebooted for two weeks, and devices have been staying connected/reporting/responding for the last week or so. So one week w/no reboots but still having issues, then for some reason something sorted itself out last week I'm back to the "no worries, just works" Zigbee network I had back on my C7. I've been able to add new devices w/out triggering problems.
The goodness started happening on/after the day I updated the C8 to the .152 release, but there was nothing in that release that should have affected general Zigbee mesh stability/reliability, so that seems like a coindence. Maybe all the hub needed at that point was a reboot, which the update process provided.
I hope my luck continues. Just in time, as my wife's sister's family is descending upon us at the end of the week for five days, and I just don't need problems/odd failures while they are here. WAF scores would plummet to new lows.
Sounds like a good time to make a mesh map (a real one, using XCTU since you've got the Xstick2) and see what a well functioning mesh looks like in your environment (noting what neighbor devices the C-8's using for routing, and what its child table looks like). If things go south again, it would be instructive to compare....
That's a great idea. I'll get it started later today and let it run until it seems to be complete.
I have to move to the office to attach my computer to some larger monitors to arrange the map. Wanted to re-confirm I can save and re-load the map later and then start dragging devices around to make it readable, correct?
Gee.. I didn't know that was possible. . . I usually wind up taking a screenshot when I get something that looks reasonable. This guide from Digi makes it seem like you can easily make a great looking map and export it; it boils down to saving an image file of what you've got, as well as the raw data.
If you don't have time to do anything else, just get a snapshot of the C-8's child table and neighbor table (the routers with the good cost figures are the ones you'll want to make note of since the others probably are irrelevant to routing). Probably good idea to note which are the parent routers of your (previously) problematic end devices too, even if you don't have time to tweak a good looking map layout (the default auto-gen'd layouts are all kind of unappealing).
